Ukraine International Airlines Flight 752 was a scheduled international passenger flight from Tehran to Kiev, operated by Ukraine International Airlines.
On the 8th of January 2020, the Boeing 737–800 operating this route crashed shortly after takeoff from Tehran Imam Khomeini International Airport.
All 176 passengers and crew were killed, making it the deadliest aviation disaster in Iran in more than a decade.
The crash surpassed Air India Express Flight 812 as the deadliest incident involving the Boeing 737-800 and places second in the number of deaths involving the Boeing 737 series, right after the Lion Air Flight 610. The crash was the first fatal aviation incident for Ukraine International Airlines since the start of its operation in 1992.
Iranian Civil Aviation Organization spokesman Reza Jafarzadeh reported shortly after the incident that a team of investigators had been sent to the crash site. The head of the commission for accidents in the Iranian CAO said that they received no emergency message from the aircraft before the crash.
It was reported that the aircraft’s black boxes (the cockpit voice recorder and flight data recorder) had been recovered, but spokesman Ali Abedzadeh said it was not clear to which country the box would be sent so that its data could be analysed.
Iran’s aviation authority has said it will not hand over the black boxes either to the aircraft’s manufacturer or US aviation authorities.
Under standard International Civil Aviation Organisation rules, America’s National Transportation Safety Board (NTSB) would participate in the investigation, as they represented the state of the manufacturer of the aircraft. France’s Bureau d’Enquêtes et d’Analyses pour la Sécurité de l’Aviation Civile (BEA) would participate as representatives of the state of manufacture of the aircraft’s engines and Ukraine’s Ministry of Infrastructure would participate as representatives of the state in which the aircraft was registered.
Given the current tensions in Iran, it is not known how these organisations would be involved, although it was reported that Iran had stated that American, French and Ukrainian authorities would be involved.
On the 8th of January, the Ukrainian government said that it would send experts to Tehran to assist with the investigation. Ukrainian President Volodymyr Zelensky instructed the Ukrainian General Prosecutor to open a criminal investigation into the crash. The Ukrainian Embassy in Iran initially said that preliminary details pointed to engine failure, but it retracted the statement shortly thereafter.
Later the same day, the Embassy said that anything was possible and refused to rule out that the aircraft was struck by a missile.
On the same day, Iran’s Road and Transportation Ministry released a statement that the aircraft burst into flames after a fire started in one of its engines, causing the pilot to lose control and crash into the ground.
According to aviation expert Vadim Lukashevich it was clear there was a fire on board, however ruling out a shootdown would be premature:
“An engine fire does not exclude the possibility that it was caused by a missile strike.”
Some aviation experts considered it too early to discuss causes. However, many did agree that the aircraft may have suffered a sudden and violent catastrophic failure, caused either by an engine failure or missile attack.
This was evidenced by the flight data that abruptly cut off during its climb, which was noted as “very unusual”.
Former inspector general of the U.S Department of Transportation Mary Schiavo criticised Iranian officials’ quick decision to declare the cause of the crash as engine failure, claiming that “there was no way for Iran to know it was engine failure,” while aviation monitoring group Opsgroup stated they “would recommend the starting assumption to be that this was a shootdown event, similar to MH17 – until there is clear evidence to the contrary”, asserting that photographs “show obvious projectile holes in the fuselage and a wing section”.
Some aviation experts also shared the same opinion that a catastrophic engine failure is very unlikely—though not impossible—to cause an aircraft to burst into flames in mid-air and crash, claiming that such incidents are very rare.
However, security sources from Western countries—three Americans, one European and one Canadian—stated that initial findings did not suggest a missile attack and rather indicated that the aircraft had a technical malfunction.